1. Field of the Invention
The present invention relates to vehicle safety devices, and more particularly to a vehicle safety exit apparatus including an auxiliary battery and a control assembly for controlling the delivery of power from the auxiliary battery to the vehicle's electric window and door lock operators during emergency situations.
2. Description of the Prior Art
Vehicles having electrically operated windows and door locks have become more prevalent due to consumers' demands for convenient vehicle options. Electrically operated window and door locks include electric DC motors coupled with the vehicle's electrical system for automatically opening or closing the windows and door locks when the vehicle's occupants activate control buttons.
Although electrically operated windows and door locks are convenient, they create potentially life-threatening safety hazards if the vehicle is involved in a collision. A vehicle's battery is typically located in the front of the vehicle's engine compartment and therefore is often destroyed or disconnected from the vehicle's electrical system when the vehicle is wrecked, especially in head-on collisions. The destruction or disconnection of the vehicle's battery disables the electrically operated windows and door locks since they are powered by the vehicle electrical system.
When the electrically operated windows and door locks fail, the occupants of the vehicle can become trapped within the vehicle since the vehicle's windows and doors are often raised and locked, respectively. Moreover, emergency personnel often cannot effectively remove the occupants from the vehicle without breaking the windows because they cannot easily unlock the doors or lower the windows. As a result, many vehicle accident victims cannot be extricated from a crashed vehicle in a timely manner, resulting in increased injuries and potential loss of life.
The problems associated with electrically operated windows and door locks are especially serious when a vehicle becomes submerged under water. Those skilled in the art will appreciate that a vehicle's electrical system nearly always fails when submerged in water. Moreover, the pressure of the water surrounding the submerged vehicle creates an inward force on the vehicle doors. This water pressure prevents the occupants from opening the doors until the vehicle's windows are lowered to equalize the pressure. However, since the vehicle's electrical system becomes inoperative when under water, the electrically operated windows cannot be lowered. Thus, many crash victims drown because they cannot open their vehicle doors or lower the windows to escape from the submerged vehicle.
Safety devices have been developed for providing a second source of power to a vehicle's electrically operated windows and door locks in the event of a main battery failure. For example, U.S. Pat. No. 4,307,789 discloses a control circuit including an auxiliary battery connected with the vehicle's main battery for operating the electrically operated windows and door locks in the event of a main battery failure.
Prior art safety devices such as the one described above suffer from several limitations that limit their utility. For example, the auxiliary battery of this type of prior art safety device is typically wired directly to the main battery. Accordingly, when the main battery is destroyed during a collision, the auxiliary battery is also often destroyed or disconnected from the vehicle's electrical system. Another limitation of prior art safety devices is that the auxiliary battery typically provides power to all of the vehicle's electrically operated windows and door locks over a single circuit. If this single circuit is damaged or disconnected in a collision, the entire safety device becomes inoperative.
A more serious limitation of prior art safety devices is that they merely provide a redundant source of power to the vehicle's electrical system but do not include means for automatically opening the windows and door locks when the vehicle electrical system fails. This is a problem because accident victims frequently become disoriented or unconscious after a collision and thus cannot operate the electrically operated windows and door locks. Thus, the mere addition of a redundant source of power to the vehicle's electrical system does not adequately solve the problem of trapped accident victims.
In view of the above-described limitations, there is a need for an improved vehicle safety exit apparatus that overcomes the limitations of the prior art.